This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. Primary support for the subproject and the subproject's principal investigator may have been provided by other sources, including other NIH sources. The Total Cost listed for the subproject likely represents the estimated amount of Center infrastructure utilized by the subproject, not direct funding provided by the NCRR grant to the subproject or subproject staff. The aim is to characterize the cellular response to DNA double strand break damage during mitosis in mamalian cells. The scope of this work will include affects on spindle checkpoint, proper segregation of chromosomes and generation of daughter cells.